Cutter blade lock



June 12, 1934.v R. R. WEDDELL CUTTER BLADE LOCK 2 sheers-sneet 1 Filed April 50, 1931 anvntoz Uune 12, 1934. R R WEDDELL 1,962,163

CUTTER BLADE LOCK Filed April so, 1931 2 Shets-Sheei 2 anocmtoz W 1?. WM

35 aumq l w. MM...

M, W/f/W Patented June 12, 1934 i 1,962,163

CUTTER BLADE LOCK Ralph R. Weddell, Shelton, Conn., assignor to ,TheO. K. Tool Company, Inc., New York, N. Y.,

a corporation of New York Application April 30, 1931, Serial No. 534,048

9 Claims. (Cl. 29-105) This invention relates to cutting tools and is radially and axially. A further distinguishing more particularly concerned with cutters of the feature of this invention is in the placing of the inserted blade type. I serrations upon the wedge member. The main It has for its primary object to provide a cutter advantage gained being that the wedges, although with insertable or replaceable blades in a manner made of a good gradeof steel, are more easily such that the tool when assembled will be exmachined than metal such as stellite, tungstenceedingly rigid and durable and capable of withcarbide or other hardened and ground high speed standing the excessive stresses of high speed pressteel which usually go intothe construction of the ent day tooling operations. blades.

10 A further object of this invention is to provide Ordinarily, the cit-setting of each blade one an improved fastening means for the blades to serration gives more than enough material for insure of their beinglocked rigidly within the the resharpening and resizing of the cutter contool head along the entire facesof the portions sequently too much blade stock is needlessly rev thereof that do not project from the cutter body, moved and the life of the blades thereby mate- 15 and as an additional refinement, to arrange the rially shortened. In combination with the comlocking devices so that toolingstresses are transpound taper blade lock hereinbefore mentioned mitted directly to the cutter body and tend more this invention contemplates a means for reducing firmly to seat the blades in the holder. the amount of material to be removed in regrind- Still another concept of this invention is to ing in order to conserve the stock and thus pro- 20minimize the amount of grinding of the; blades long the life of the individual blades. With this necessary in resharpening by constructing the end in view each series of serrations formed in blade lock in a manner necessitating but a single the successive slots in the cutter body are adjustmentto effect simultaneously a repositionstaggered, with respect to a preceding series, a ing of thebladein two directions, as for example, fraction of the increment between two serrations 25 radially and axially in the case of a face mill, so that the blades may be successively advanced slotting cutter, etc. one or more slots around the tool and in this way In carrying out the objects in accordance with move each blade outwardly from the cutter an this invention it is proposed to construct the amount sufficient for accurate regrinding to size cutter body of a suitable grade of strong tough without incurring undue waste of material.

30 material and provide at its outer end or periph- This invention further contemplates a proerythereof, as the case may be, a dove-tail slot vision for adjusting the blade outwardly in one for the reception of a similarly formed cutting direction only in order to effect major changes in blade. One wall of the slot is also inclined toward the width of the slot to be cut, if the invention is the wall opposite thereby forming an opening applied to a slotting tool, or to eiTect major ad- 35 tapered in transverse directions. A tapered I 'justments in thediameter of the cutter, if the wedge, having an interlocking engagement with invention beapplied to a tool of the face mill type. the blade, fits snugly between the blade and the For this purpose one of the members, either blade wall of the slot and when assembled and driven or wedge, is provided with one or more projections in placesecurely locks the blade against movewhich are adapted to interfit with and engage 40 ment. complemental cavities formed in the other mem- Toincrease the frictional resistance to wedge her and by adjusting one member relative to the movement and to provide a positive means for other, the blade will, when re-inserted, project making fine adjustments of the cutter blades, one more or less from the holder according to the face of the wedge member is provided with a pluincrement between, or the spacing or arrange- 45 rality of .V-shaped serrations, extending in the ment of, the interlocking devices.

direction of its taper, and which are adapted to A positive interlock between wedge and blade interfit with cooperating serrationsformed in has the further advantage of preventing relative the adjacent wall of the cutter ,body. For exmovement between the two members and thereby ample, the cutter tooth and wedge may be reprevents the blade from shifting its position un- 50 moved from its socket and reinserted set over der load. The wedge member being tapered in from its former position a distance equal to the the direction of the/end thrusts upon the tool width of the number of serrations intervening, and being interlocked with the blade has a tendand thus, because of the mutual inclination of the ency to move furtherinwardly and thus impinge intersecting planesof the two side walls, the posi upon the blade member more firmly to hold it w 55 tion of the blade is m seums be changed both in its seat. v

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplated by this invention, drawings depicting a. preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of referencedenote corresponding parts throughout all the views, of which: I

Figures 1 and 2 represent end and side views respectively of a face mill embodying this invention. Figs. 3, 4 and 5 are top, side and end views of a cutter detached from the holder. Figs. 6, 7 and 8 represent top, side and end views of the wedge member, likewise detached from the holder. Fig. 9 is an enlarged portion of a cutter more clearly illustrating the manner of effecting radial adjustment of the blades in a circular tool. Fig. 10 is a side view thereof illustrating the effect of a radial adjustment upon the axial position'of the blade. Fig. 11 is a sectional view illustrating one form of blade and wedge interlock and the effect of moving the blade with respect to the wedge one or more positions to effect a major adjustment or to compensate for numerous regrindings. Fig. 12 is an end view of Fig. 11. Figs. 13 and 14 represent an adaptation of this invention to single point tools, such as lathe, planer or shaper tools, fly cutter, etc., but it will be understood, however, that its use in broaches, gang tools, etc., is also contemplated.

Referring more particularly to Figs. 1 and 2,'

the invention is shown therein as applied to a face mill comprising a base or body member 1 formed of a metal having the necessary characteristics for tools of this character and which obviously need not be of such high grade of steel as that of the blade. About the periphery of the body 1 a number of double tapered slots 2 are provided for the reception the blades 3 and wedges 4 which together form units complementally tapered.

Details of a representative blade and wedge are depicted in Figs. 3 to 8 inclusive, and in this particular type of cutter the blade is tapered radially, the side a being inclined with respect to the side b approximately an angle of 2, the wider portion of the blade forming the base or part nearest the axis of the cutter. Along its major axis, the faces a and b of the blade are parallel as illustrated in Fig. 3.

The wedge member 4 is tapered transversely to the blade, that is, surfaces (1 and d are arranged parallel to each other (radially with respect to the axis of the cutter) but tapered in a direction substantially paralleling the cutter axis, as shown by Fig. 6. The angle of taper need only be great enough to impinge the blade tightly against the adjacent wall e of the slot in the holder but not so great as to work loose under the vibrating effects of a tooling operation. As herein shown the angle of taper on the wedge approximates 5", which has been found to be highly satisfactory, permitting easy assembling and disassembling as well as to securely hold the blade in place while under load.

It will be observed that the radial thrusts acting upon the blade tend to move the same inwardly (toward the center). Movement in this direction, however, is prevented by means of an overhanging portion or ledge 5 provided by the wedge member which forms an abutment or base upon which the blade seats. Radial movement of the blade outwardly is also prevented by reason of the dove-tailed formation of the blade and slot.

So that the wedge member does not move radially inleither direction, a series of serrations 6 extending in the general direction of the taper are formed upon the wedge and which are adapt ed to interflt with a similar series of serrations 7 formed on the side wall of the slot in the holder. Thus, the blade is held positively against radial movement and the radial forces acting thereupon are transmitted first to the wedge thence to the cutter body.

Axial movement of the blades with respect to the holder is largely if not entirely prevented because of the impinging effect of the wedge member and the friction between surfaces a--e and 0-12, however, as an additional measure, means are provided for positively locking the wedge and blade against relative movement. The detail Figs. 4 and 7 illustrate one such form of lock which comprises a pin or abutment 8 carried preferably by the wedge member and one or more complementally formed grooves 9 formed in'the other member. When the blade and wedge are placed with their faces b and 0 together, the pin 8 engages one of the grooves 9 and prevents the parts from moving axially relatively to each other.

The two part double tapered unit thus formed is then inserted inthe slot in the holder and tapped gently in place. The assembled cutter is next ground to size and is ream for operation.

After a period of usage the blades will become dulled and must be resharpened if accuracy and good work are to be maintained. Figs. 9 and 12 illustrate how fine adjustments of the blades can be made without sacrificing any of the strength of the cutter nQrincurring undue waste of material. The compounded unit 3-4 is removed from the holder and set-over one or more serrations radially and again reinserted. The stepping over of the compoundly tapered .unit toward the converging walls of the slot, increases the diameter of the cutter as well as its length or width as the case may be, for the reason that the slot being smaller the blade and wedge will not enter the holder as great a distance. Consequently, the component of the double tapers effects an axial repositioning of the blade sufficient to allow for regrinding and truing to size.

Extremely fine adjustments of the blades may also be effected if each series of serrations 7 is cut in the holder slightly off-set from a succeeding series by an amount equal to a fraction of the increment between two serrations, and then successively advancing the compounded units one or more slots. In this way each unit projects only a fraction of the increment between two serrations and exceptionally close adjustments in size may be made. Fig. 9 represents a portion of a rotary cutter in which for the purpose of illustration depicts a series of blades stepped out unequal distances better to illustrate the ease at which radial adjustments may be made. Fig. 10 is a projection of Fig. 9, showing how radial adjustment of the blades effects also an axial adjustment thereof. The staggering or off-setting of the serrations in the cutter body for attaining fine adjustment radially, likewise eifects finer adjustments axially when the blades are successively advanced.

A further refinement of this invention lies in the fact that adjustments of the blades in one di- 1,962,163 rection may be made without disturbing the transverse adjustment. Fig. 11 illustrates clearly how this may be accomplished, and in which the dotted line position of theblade represents its original size and the full line position the size after a number of regrinding operations have been performed thereon and the blade moved outwardly one or more of the notches 9. The

blade per se, not being tapered in this direction (axially of the cutter) permits of such an adjustment relative to the wedge 4 without changing its position radially. Owing to its comparative inexpensiveness the blade and wedge are formed preferably with the pin and slot connection as shown but it will be understood, however, that other forms of interlockingarrangements are contemplated. For example, the lower edge of the blade and the engaging face 5 of the abutment may readily be provided with complemental and interfltting serrations whereby finer adjustments of the blades in one direction may be easily effected in the same manner as previously explained.

Obviously, this form of inserted blade and lock is adaptable to other types of tools such as left and right handed or faced cutting tools, single or multi-point. Figs; 13 and 14 illustrate its application to a single point tool and in which theposit unit having compound tapers commensurate with the tapers ofthe slot formed in the holder.

The terms compoundly tapered opening, an

opening having compoundly inclined" side walls,

a double tapered" opening, transversely ta pered as herein used are intended to mean an opening or a member, at least two of the side walls of which are inclined with respect to each other, or are tapered in two or'more directions. In the case of a rotary cutter, for example, the tapers of the blade opening would ordinarily extend radially and axially of the cutter body, while in thecase of a single point tool, such as a lathe tool, the tapers of the blade opening would ordinarilyextend in the direction of the general axis of the holder and, also, in a direction perpendicular thereto. In either of the above examples it will be seen, that the two tapers extending in transverse directions afford a-compoundly tapered" opening.

Without further analysis, the foregoing will so fully reveal the, gist of this invention that others can, by applying current knowledge, readily adapt it for various utilizations by retaining one or more of the features that, from the'standpoint of the prior art, fairly constitute essential characteristics of either the generic or specific aspects of this invention and, therefore, such adaptations should be, and-are intended to be,

comprehended within the meaning and range of equivalency of the following claims:-

Having thus revealed this invention, 1 claim as new and desire to secure the following combinations and elements, or equivalents thereof, by Letters Patent of United States:-

.1. An inserted blade metal cutting tool combining, a holder member provided with an openinghaving two of its side walls transversely inclined with respect to each otherso that a compoundly tapered opening is provided; a composite unit adapted to be pre-assembled and inserted within said opening, said unit comprising a tapered blade member and a tapered wedge member, the tapers on said members extending in transverse directions; and means including a ledge portion provided'by said wedge member adapted to provide a seat for said blade for looking said members together when the unit is inserted in said holder.

2. An inserted blade metal cutting tool combining, a holder member provided with an aperture having compoundly inclined side walls; a composite unit adapted tobe pre-assembled and inserted within said opening, said unit comprising a tapered blademember and a tapered wedge member, the tapers on said members extending in transverse planes; and interlocking means comprising a ledge portion provided by said wedge and a pin and slot connection between said blade and wedge-for maintaining said mem-. bers in predetermined relation to each other when the composite unit is inserted in said aperture.

3. An inserted blade tool combining a holder member provided with an aperture having compoundly inclined side walls; a blade member insertable in said opening and having one wall thereof inclined at an angle corresponding to the angle of inclination of one of the walls of said aperture; 9. locking member insertable within said aperture adjacent said blade and having one side thereof inclined at an angle corresponding to the angle of inclination of the adjacent wall of said apertureyand interlocking means between contacting portions of said blade and wedge adapted positively to lock saidmembers. against relative movement in transverse directions.

4. An inserted blade tool combining a holder member having a double tapered opening formed therein; a blade member insertable in' said opening and having one wall thereof inclined at an angle corresponding to the angle of inclination of one of the walls of said opening; a locking member insertable within said opening adjacent said blade andhaving one side thereof inclined at an angle corresponding to the angle of inclination of the other inclined wall of said aperture; and an adjustable connection between said blade and said locking member for locking said members against relative movement in transverse directions. 180 5. A composite cutter blade for metal working tools adapted to be removably mounted in a com poundly tapered opening formed in a suitable holder comprising a tapered blade member and a tapered locking member, the taper'on said looking member'extending in a direction perpendicular to the direction of taper on said blade; and means maintaining the two members inv a predetermined position relative to each other comprising a blade seat formed upon the locking member and a blade locating stud formed on said seat, said stud being adapted to engage a recess in the said blade and to cooperate-with said seat to prevent relative movement between ing means therefor, said means comprising a wedge shaped member the taper 01' which extends in a direction perpendicular to the direction of the taper formed on said blade; and interengaging means between said blade and wedge members comprising a blade seat formed upon the wedge member and a pin and recess connection between adjacent face portions of said blade and wedge adapted when engaged to positively maintain the blade in an adjusted position radially and axially of said holder member.

7. An inserted blade metal cutting tool combining, a holder member provided with a compoundly tapered opening; a composite unit insertable within said opening, said unit comprising a tapered blade member and a tapered wedge member, the tapers on said members extending in transverse directions; a blade seat formed on s'aid-wedge'member; and interlocking means between said blade and said seat portion for maintaining said blade member in adjusted position.

8. A cutter tool of the inserted blade type combining a holder member provided with a 'compoundly tapered opening; a tapered composite unit insertable in said opening, said unit comprising a blade member and a locking member, which together form a unit tapered in conformity with the compoundly tapered opening; means for adjusting said blade member with respect to said holder in two directions, comprising a series of serrations formed upon the wall of said locking member and the adjacent wall of the opening in the holder and an abutment element provided by one of the members of said composite unit adapted to engage the other member of said unit for maintaining said members in a predetermined position in said holder.

9. A cutter tool according to the preceding claim characterized by the provision of interengaging means between the members of said composite unit for positively locking said members against lateral movement relative to each other.

RALPH R. WEDDELL. 

